DLBCL Cases Research Articles

Utility of clinical, laboratory, and lymph node MYD88 L265P mutation in risk assessment of diffuse large B-cell lymphoma patients

BackgroundDiffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma and is characterized by heterogeneity in biology and clinical behavior. Mutations in the myeloid differentiation primary response 88 (MYD88) are found in different lymphoproliferative disorders and are associated with variable clinical and prognostic impact.AimTo investigate the frequency of MYD88 L265P mutation and its clinical impact in a cohort of Egyptian DLBCL patients.MethodsFFPE lymph node samples from 87 DLBCL patients (46 males / 41 females; median age, 58 years) were included and analyzed for MYD88 L265P by an allele-specific PCR.ResultsMYD88 L265P mutations were found in 52 patients (59.8%) out of 87 DLBCL cases. Patients with L265 mutation were significantly younger than non-mutated patients (p = 0.022). None of the patients with the L265P mutation showed a significant association with the clinical parameters of DLBCL. Interestingly, MYD88 L265 mutated patients were found to be significantly correlated with HCV infection (p = 0.037). The median follow-up time across the entire cohort was 26 months. Univariate analysis showed that overall survival (OS) was affected by gender, LDH level, and CNS-IPI scoring (p = 0.048, 0.008, and 0.046, respectively), while disease-free survival (DFS) was affected by B symptoms and LDH level (p = < 0.000 and 0.02, respectively). However, the MYD88 mutation status and other prognostic factors showed no association with OS or DFS.ConclusionsOur findings indicate a high frequency of MYD88 L265P mutations in our study population and not associated with prognostic markers or the outcome of the disease.

S5185 Gastric Perforation: An Unexpected Case of DLBCL

S5185 Gastric Perforation: An Unexpected Case of DLBCL

Loncastuximab Tesirine in the Treatment of Relapsed or Refractory Diffuse Large B-Cell Lymphoma.

Currently, a significant percentage of patients with DLBCL are refractory or relapse after a first line of immunochemotherapy. Second relapses after autologous stem cell transplantation or chimeric antigen receptor T-cell therapies present few treatment options and do not yield good results. New molecules have entered the immunotherapy arsenal. Loncastuximab tesirine comprises a humanized anti-CD19 monoclonal conjugated antibody, which consists of an anti-CD19 antibody and cytotoxic alkylating agent, SG3199. Several studies have proven its efficacy in the treatment of refractory cases of DLBCL with a good safety profile, with the main adverse effects being neutropenia, thrombopenia, and liver enzyme involvement. In this review, we explain the mechanism of action of this molecule, the clinical data that have led to its acceptance by the FDA, and the new therapeutic options that are proposed in association with this drug.

Semimethylation is a feature of diffuse large B-cell lymphoma, and subgroups with poor prognosis are characterized by global hypomethylation and short telomere length

BackgroundLarge B-cell lymphoma (LBCL) is the most common lymphoma and is known to be a biologically heterogeneous disease regarding genetic, phenotypic, and clinical features. Although the prognosis is good, one-third has a primary refractory or relapsing disease which underscores the importance of developing predictive biological markers capable of identifying high- and low-risk patients. DNA methylation (DNAm) and telomere maintenance alterations are hallmarks of cancer and aging. Both these alterations may contribute to the heterogeneity of the disease, and potentially influence the prognosis of LBCL.ResultsWe studied the DNAm profiles (Infinium MethylationEPIC BeadChip) and relative telomere lengths (RTL) with qPCR of 93 LBCL cases: Diffuse large B-cell lymphoma not otherwise specified (DLBCL, n = 66), High-grade B-cell lymphoma (n = 7), Primary CNS lymphoma (n = 8), and transformation of indolent B-cell lymphoma (n = 12). There was a substantial methylation heterogeneity in DLBCL and other LBCL entities compared to normal cells and other B-cell neoplasms. LBCL cases had a particularly aberrant semimethylated pattern (0.15 ≤ β ≤ 0.8) with large intertumor variation and overall low hypermethylation (β > 0.8). DNAm patterns could not be used to distinguish between germinal center B-cell-like (GC) and non-GC DLBCL cases. In cases treated with R-CHOP-like regimens, a high percentage of global hypomethylation (β < 0.15) was in multivariable analysis associated with worse disease-specific survival (DSS) (HR 6.920, 95% CI 1.499–31.943) and progression-free survival (PFS) (HR 4.923, 95% CI 1.286–18.849) in DLBCL and with worse DSS (HR 5.147, 95% CI 1.239–21.388) in LBCL. These cases with a high percentage of global hypomethylation also had a higher degree of CpG island methylation, including islands in promoter-associated regions, than the cases with less hypomethylation. Additionally, telomere length was heterogenous in LBCL, with a subset of the DLBCL-GC cases accounting for the longest RTL. Short RTL was independently associated with worse DSS (HR 6.011, 95% CI 1.319–27.397) and PFS (HR 4.689, 95% CI 1.102–19.963) in LBCL treated with R-CHOP-like regimens.ConclusionWe hypothesize that subclones with high global hypomethylation and hypermethylated CpG islands could have advantages in tumor progression, e.g. by inactivating tumor suppressor genes or promoting treatment resistance. Our findings suggest that cases with high global hypomethylation and thus poor prognosis could be candidates for alternative treatment regimens including hypomethylating drugs.

Reduced Immune-Cell Infiltration in MHC Class I Negative DLBCL

Background Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy and the most common type of non-Hodgkin B-cell lymphoma. It is a genetically, biologically and clinically heterogeneous disease and current research focuses on identifying stratification biomarkers to identify high-risk patients and guide selection of therapy. The genetic landscape of DLBCL is well characterized, but how these mutations affect the lymphoma microenvironment is not fully understood. We aimed to categorize DLBCL cases based on tumor microenvironment (TME) features and to identify how tumor cell features including loss of MHC expression shape the TME. Methods Diagnostic biopsies from 58 high-risk de novo DLBCL NOS from two Nordic phase II clinical trials (PMID: 32380536, PMID: 23247661) were imaged by Hyperion imaging mass cytometry. Single-cell segmentation was followed by clustering of 14 lineage markers and manual annotation to identify eight cell types. Using CytoMAP (PMID: 32320656), the cells were divided into 20-µm-radius neighborhoods and clustered to define six types of tissue regions (Figure 1). Unsupervised hierarchical clustering of the region prevalence in each image was used to classify different types of tumor microenvironments. To identify tumor cell features, tumor-specific expression of markers related to immune evasion (CD54, PD-L1) and prognostic markers (FOXP1, Ki67) were quantified by manual gating of positive cells. Cases were classified as MHC class I loss when less than 50% of the tumor cells expressed HLA A or HLA B, and Ki67-positive when more than 10% of the tumor cells were gated as positive. The LymphGen algorithm was used to classify tumor genotypes. Results Clustering of the region prevalence in each image revealed six types of tumor microenvironments; immune-cell depleted (47%), tumor/immune cell mixed (29%) and four TMEs with low tumor-cell fractions that were dominated by CD4 T cells (7%), CD8 T cells (7%), M1/M2 macrophages (5%) or collagen-positive stromal cells (5%). In cases classified as immune-cell depleted, more than 70% of the cells were tumor cells and less than 15% were infiltrating immune cells. The four groups with low tumor-cell fractions were merged for statistical analyses. TME subclasses were not correlated with tumor genotypes, but DLBCL cases classified as immune-cell depleted were overrepresented among the Ki67-positive cases. Loss of MHC class I was seen in 34% of the cases and was associated with the immune-cell depleted TME subclass. Furthermore, MHC class I loss correlated with lower infiltration of CD4 and CD8 T cells. Tumor-cell specific expression of MHC class II, PD-L1, CD54, or FOXP1 did not significantly correlate with the TME subclasses. Conclusion In conclusion, our study contributes to improved understanding of the DLBCL microenvironment through mapping of the diversity of immune-cell composition. We found that loss of MHC class I expression was associated with an immune cell-depleted TME. The prominent loss of MHC has potential impact for the selection of patients for CAR T-cell therapy vs. bispecific antibodies/T-cell engagers. Together, refined classification tools of DLBCL based on genetic aberrations and microenvironment architecture may improve strategies of personalized medicine.

Assessment of the Expression of Genes Related to Epigenetic and Chromatin Modifications in Diffuse Large B-Cell Lymphoma Patients Resistant to R-CHOP

Introduction Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. The mainstay of frontline therapy remains R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) or R-CHOP-like immunochemotherapy. Patients' responses to R-CHOP therapy vary depending on the stage and/or molecular subtypes of DLBCL. Approximately 40% of advanced-stage DLBCL patients suffer from a refractory or relapsed disease[1]. The outcome for patients with early relapses after rituximab-containing first-line therapy remains poor[2]. DLBCL poses a marked degree of genetic heterogeneity. Here, we compare the expression of genes related to epigenetics and chromatin modifications in DLBCL patients resistant and non-resistant to R-CHOP therapy. Objective The aim of this study is to assess the differences in the expression of genes related to epigenetics and chromatin modification in DLBCL patients that could lead to chemoresistance and failure of R-CHOP treatment. Method The gene expression profile (GEP) was obtained from Gene Expression Omnibus (GEO) database (Accession number: GSE173263) submitted by Dlouhy et al[3]. The GEP was analyzed in DLBCL cases, including 10 early failure cases (defined as refractory to induction treatment or early relapsing (&amp;lt;12 months from diagnosis)) and 29 responding patients, to identify features associated to primary chemoresistance. The comparison was done using the list of genes proposed by Bakhshi, T. et. al[4] , where he selected the genes that were identified to potentially cause epigenetic and chromatin modifications in DLCBL. All the comparisons were done using a T-test. Results There were significant differences in the gene expression related to epigenetics and chromatin modifications between DLBCL patients in the early failure arm versus the remission arm. Patients who had early failure to R-CHOP tended to have higher expression of these genes: SMARCA4 (p=0.010), SETD1B (p=0.018), SETD2 (p=0.024), EP300 (p=0.012), MLL3 (p=0.049), INO80 (p=0.001), CHD8 (p=0.007), NCOR1 (p=0.020), ARID1B (p=0.034), and SETD5 (p=0.007). Compared to the patients who were in remission after R-CHOP therapy, these patients had significantly higher expression of HIST1H1E (p=0.007). Conclusion Gene expression related to epigenetics and chromatin modifications significantly impacts the prognosis of DLBCL patients treated with R-CHOP. Differences in gene expression may lead to chemoresistance, and higher expression levels are associated with a worse prognosis. This study sheds light on the importance of chromatin and epigenetic modifications in DLBCL progression, guiding the development of future therapies.

Genetic Subtyping Using Whole Exome Sequencing across Large B Cell Lymphoma Entities in a Series of 109 DLBCL and Plasmablastic Lymphoma Cases

Background: Diffuse Large B Cell Lymphomas are still a significantly heterogeneous disease with few molecularly defined entities. Recently genomic based algorithms have been proposed for DBCL NOS disease classification, including the Lymphgen tool 1. Other large B cell lymphoma entities, including High Grade BCL Dual Hit or plasmablastic lymphoma remain poorly characterized according to this molecular based clustering methods. Here we sought to apply this tool for disease classification in a series of 109 large B cell lymphoma cases derived from GELTAMO clinical trials (NCT01848132 and NCT2015-005390-21) and retrospective multicentric series to confirm its application across different large B cell lymphoma entities. Methods: We retrieved FFPE and liquid biopsy diagnostic samples from 109 cases and performed histopathological confirmation, FISH testing and whole exome sequencing (Agilent Sureselect v6) by NGS. Sequencing data and available fusion data for BCL2 and BCL6 were used to classify the cases according to Lymphgen (https://llmpp.nih.gov/lymphgen). Results: 109 cases were classified as different large B cell lymphoma entities, including 31 DLBCL NOS GCB type, 8 HGBCL/DLBCL DH/NOS, 41 DLBCL NOS non-GCB type, 22 plasmablastic lymphoma, 3 THRLBCL, 1 PMBL, 2 DLBCL NOS and 1 3B Follicular Lymphoma. After WES median Tumor Mutation Burden was 972. Overall genetic classification by Lymphgen was obtained in 53 cases (49%) with the remaining 56 cases considered unclassified (molecular subtype other/NOS). Of the genetically identified cases, 18 were classified as ST2 (33%), 15 were considered EZB (28%), 5 BN2 (10%) and 3 MCD (5%). Interestingly 12 (22%, overall, 11%) were genetically composite, including 8, ST2/EZB; 1, ST2/BN2; 1, ST2/MCD and 2 ST2/EZB/MCD. According to histopathological subtype 17 GCB type DLBCL were classified as EZB (8, 47%), ST2 (5, 30%) and BN2 (1, 6%). 3 cases (17%) were genetically composite. 6 out of 8 cases of HGBCL/DLBCL DH/NOS were classified as either EZB (2), ST2 (2) or composite EZB/ST2 (2). 19 non-GCB type DLBCL were classified as ST2 (5, 26%), BN2 (4, 21 %), EZB (3, 16 %) and MCD (3, 16%). 4 cases were genetically composite (21%). Interestingly, plasmablastic lymphomas showed ST2 genetic features, found in 5 out of 22 (23%) and composite ST2/EZB in 2 cases. Genes overrepresented in the ST2 cluster include TET2, PRRC2C, STAT3,DOCK8 and CLTC. Plasmablastic Lymphomas classified as other showed recurrent mutations in PRRC2C, PABPC1, TRRAP, PRKCB, EP300 and TP53. Conclusions: ST2 and EZB genetic groups stand as the most frequent genetic subtypes of DLBCL NOS. While ST2 is found in either GCB and non-GCB subtypes, EZB is found preferentially in cases with the GCB phenotype, including GCB type DLBCL and HGBCL/DLBCL DH. In comparison with already published series we found a relatively higher prevalence of the ST2 genetic subtype among DLBCL NOS. MCD and BN2 genetic subtypes are restricted to the non-GCB subtype, but its prevalence is relatively low. Importantly, a significant fraction of cases (~50%) is still genetically unclassified (molecular subtype NOS) using WES and FISH-derived fusion data. Proper identification of the A53 cluster and relevant dysregulated pathways in the molecular NOS group require more research. Specific large B cell lymphoma entities such as plasmablastic lymphoma show features of ST2 genetic subtype in a significant fraction of tumors. These features include JAK/STAT3 pathway activation related genes and fit well with already published data 2,3. In addition, recurrent mutations in TET2, involved in epigenetic regulation of gene expression and TRRAP, target of C-MYC transcriptional activation, were enriched in this molecular subtype of plasmablastic lymphoma. Importantly ~70% remained unclassified. Mutations in this group are recurrently found in PRRC2C as well as PABPC1, both involved in VEGFA-VEGFR2 signaling. In summary, DLBCL NOS molecular subtyping supplies exact molecular classification in ~50% of our cohort. ST2 and EZB subtypes constitute ~60% of the cases with a fraction of ~15% of composite ST2/EZB. Application of the molecular classifier to plasmablastic lymphomas shows intraspecific genetic diversity and points toward dysregulation of JAK/STAT, MAPK/Erk and VEGFA-VEGFR2 signaling as well as MYC transcriptional activation. REFERENCES 1. PMID: 32289277 2. PMID: 33225311 3. PMID: 32273478

GRK2, an Inhibitor of MALT1-Dependent Oncogenic Signaling, Is Downregulated By microRNA in ABC-DLBCL

Background: The “CBM” complex, composed of the scaffolding protein CARMA1, the adaptor protein BCL10, and the effector protein MALT1, performs multiple pivotal functions as a mediator of antigen receptor-dependent induction of the NF-κB transcription factor and subsequent lymphocyte activation. The effector molecule of the CBM complex, MALT1, regulates downstream signaling via two important functions: first, as a scaffold to recruit and activate components of the canonical NF-κB signaling machinery, and second, as a protease to enzymatically cleave and inactivate multiple substrates including several negative regulators of NF-κB signaling. Deregulated/constitutive activation of MALT1, which can result from gain-of-function mutations in either B cell receptor (BCR) or CARMA1 or from chromosomal translocation involving the MALT1 gene, underlies the pathogenesis of a variety of lymphoid malignancies including activated B-cell type-diffuse large B-cell lymphoma (ABC-DLBCL) and mucosa associated lymphoid tissue (MALT) lymphoma. We recently discovered that G-protein-coupled receptor kinase 2 (GRK2) binds to MALT1 and inhibits MALT1 scaffold and proteolytic activities. Further, we found that knockdown of GRK2 in ABC-DLBCL enhances tumor growth in vivo, suggesting that GRK2 may act as a tumor suppressor in MALT1-dependent lymphomas. Interestingly, we found that GRK2 mRNA levels are markedly lower in a subset of DLBCL cases in comparison to normal B cell controls and that lower GRK2 level is associated with reduced survival in ABC-DLBCL patients. We thus sought to investigate how GRK2 expression is regulated in ABC-DLBCL. Methods and Results: We surveyed 6 published DLBCL sequencing datasets (334 cases total) and identified only one case with a mutation/deletion in the ADRBK1 (GRK2) gene. Thus, we concluded that mutation/deletion could not account for the lower levels of GRK2 in a subset of DLBCL cases. We next investigated other potential mechanisms that could play a role in downregulating GRK2 in ABC-DLBCL, including the impact of microRNA (miRNA). Using DICER-knock-down (KD) and knock-out (KO) HEK 293T cells, we demonstrated that GRK2 protein level significantly increases when miRNA processing is impaired. Next, we performed a bioinformatic analysis which identified two candidate microRNAs, miR-148b and miR-331, whose levels inversely correlate with GRK2 mRNA in ABC-DLBCL patient tumor specimens. These two microRNAs were also identified among the top four candidate hits (miR-125b, miR-148b, miR-125a and miR-331) using mirDIP, a microRNA Data Integration Portal which we used to screen for candidate miRNAs predicted to target the 3'UTR of GRK2. We confirmed direct targeting of GRK2 by three top candidate miRNAs, miR-148b, miR-125a and miR-125b, using a GRK2 3'UTR reporter assay. Notably, we found that expression of these three microRNAs is higher in ABC-DLBCL cells (OCI-Ly3 and TMD8), which demonstrate lower GRK2 mRNA expression in comparison to primary B cells. We showed that overexpression of either miR-125a, miR-125b or miR-148 in OCI-Ly3 and TMD8 cells leads to reduced GRK2 protein level, increased MALT1 scaffolding and proteolytic activities and enhanced ABC-DLBCL cell proliferation. Conversely, anti-miRNA Locked Nucleic Acids (LNA) inhibitors of miR-125a, miR-125b or miR-148 each inhibited ABC-DLBCL cell proliferation and MALT1 activity. Further evaluation of the effect of anti-miRNA LNA inhibitors on tumor progression is under way, using an ABC-DLBCL xenograft animal model. Conclusions: Together, our data show that specific miRNAs (miR-148b, miR-125a and miR-125b) down-regulate GRK2 expression in ABC-DLBCL, which in turn enhances MALT1 scaffolding and proteolytic activities, leading to increased tumor cell proliferation. Future studies investigating miRNA inhibitors which enhance GRK2 expression and thereby suppress MALT1 activity may inform novel strategies for inhibiting MALT1-dependent lymphomagenesis.

Novel Targeted Agents in Combination with R-ICE (R-ICE-X) Based on Genotyping in Relapsed/Refractory DLBCL

Background: Relapsed/refractory (R/R) DLBCL constitutes 40% of all DLBCL cases. Coventional salvage regimens, such as R-ICE, R-GDP, and R-DHAP, have an overall response rate (ORR) of 60% and a complete response rate (CR) of 30-40%. For patients who have achieved complete metabolic remission as determined by PET-CT evaluation after salvage therapy, undergoing autologous transplantation is crucial in order to achieve durable long-term survival. The outcomes of these R/R DLBCL remain to be improved. Aims: This prospective study aims to investigate whether adding novel agents to R-ICE (R-ICE-X) based on genetic subtypes could improve clinical efficacy in R/R DLBCL. This trial is registered at clinicaltrials.gov (NCT05348213). Method:In this study, patients with R/R DLBCL aged 18 -75 years were enrolled. All patients were assigned and stratified by genetic subtype and received different targeted agents combined with R-ICE. The efficacy was evaluated after 3 courses of R-ICE-X (every 21 days). Patients with CR/PR were subsequently treated with autologous hematopoietic stem cell transplantation or 3 courses of R-ICE-X consolidation and lenalidomide maintenance for up to 12 months. See the detail in the figure. The primary endpoint was the overall response rate (ORR), and the secondary endpoints were the 2-year progression-free survival (PFS) rate, 2-year overall survival (OS) rate, and safety evaluation. Results: At the time of data cut-off, a total of 66 patients were enrolled, with a median age of 61(20-75) years. In the patients with R-ICE-zanubrutinib group (n=28), the ORR was 84.0%, with 15 patients (15/25, 60.0%) achieved CR and 6 patients (6/25, 24.0%) achieved PR. The 1-year PFS rate and OS rate were 68.2% and 90.5%, respectively. In the patients with lenalidomide combined with R-ICE (n=28), 16 patients (16/26, 61.5%) achieved CR, 4 patients (4/26, 15.4%) achieved PR, and the ORR was 76.9%. The 1-year PFS and OS rates were 78.5% and 100.0%, respectively. In the patients with the R-ICE-decitabine group (n=7), the ORR was 66.7%, with 4 patients (4/6, 66.7%) achieving CR. The 1-year PFS rate and OS rate were 50.0% and 60.0%, respectively. The number of other groups needs to be further updated. Among 66 patients, 17 patients had autologous transplantation (ASCT) and 1-year PFS and OS of patients with ASCT were both 87.1%. The number of other groups will be further updated. Conclusion: Novel targeted agents in combination with R-ICE (R-ICE-X) regimen was well tolerated and efficacy in R/R DLBCL patients, meanwhile, it could be a promising bridging regimen for ASCT. The study is ongoing and further results will be continuously released.

Clinical boundaries in adult cases of large B cell lymphoma with IRF4 rearrangement.

Large B-cell lymphoma with IRF4 rearrangement (LBCL-IRF4) is a recently described entity included in the revised 4th edition of the WHO Classification of Haematolymphoid Tumours (2017). Here we highlight the difficulties in classification of those cases which arise in adult patients with unusual clinical features. We present three cases with morphological and immunohistochemical features consistent with large B-cell lymphoma arising in adult patients, which were found to have isolated IRF4 rearrangements on FISH analysis. Each patient presented with advanced-stage disease and had a history of immunosuppression; clinical features that are not typical of LBCL-IRF4 and which make the distinction from DLBCL, not otherwise specified (NOS) challenging. We propose that the clinical boundaries of LBCL-IRF4 arising in adult patients need further delineation to allow distinction from true cases of DLBCL, NOS.

Pseudotemporal ordering of spatial lymphoid tissue microenvironment profiles trails Unclassified DLBCL at the periphery of the follicle.

We have established a pseudotemporal ordering for the transcriptional signatures of distinct microregions within reactive lymphoid tissues, namely germinal center dark zones (DZ), germinal center light zones (LZ), and peri-follicular areas (Peri). By utilizing this pseudotime trajectory derived from the functional microenvironments of DZ, LZ, and Peri, we have ordered the transcriptomes of Diffuse Large B-cell Lymphoma cases. The apex of the resulting pseudotemporal trajectory, which is characterized by enrichment of molecular programs fronted by TNFR signaling and inhibitory immune checkpoint overexpression, intercepts a discrete peri-follicular biology. This observation is associated with DLBCL cases that are enriched in the Unclassified/type-3 COO category, raising questions about the potential extra-GC microenvironment imprint of this peculiar group of cases. This report offers a thought-provoking perspective on the relationship between transcriptional profiling of functional lymphoid tissue microenvironments and the evolving concept of the cell of origin in Diffuse Large B-cell Lymphomas.

Relationship Between Clinical Factors of Lymphoma DLBCL GCB and Non-GCB Subtype with Ki-67 Proliferation Index in Siloam Karawaci Hospital 2014 - 2018

&lt;p&gt;&lt;strong&gt;Background:&lt;/strong&gt; Non-Hodgkin large cell B-lymphoma (DLBCL: Diffuse Large B-cell Lymphoma) were classified into two subtypes of Germinal Center B-Cell Like (GCB) and non-Germinal Center B-Cell Like (non-GCB), which GCB has a better prognosis. The Ki-67 antigen is one of the most reliable markers of cell proliferation. This research aims to establish the relationship between proliferation index Ki-67 with DLBCL subtypes and to evaluate the utility of Ki-67 proliferative index as a predictive marker for predicting stages of lymphoma.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;We obtained 60 cases of patient samples DLBCL in Siloam Hospital Lippo Karawaci in 2014-2018. Clinical and pathological data were obtained from medical records. Chi-square methods were used to analyze data.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Result:&lt;/strong&gt; There were more ≤60 years compared to &amp;gt;60 years. In this study, there were more male patients than female patients. lymphoma provided in extranodal were higher than lymphoma in nodal form.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; There is a relationship between Ki-67 proliferation index with lymphoma GCB and non-GCB subtypes and stage of lymphoma, which can be used as a predictive factor in predicting the stage of lymphoma.&lt;/p&gt;

Primary Extranodal Non-Hodgkin Lymphoma of Cheek

Non-Hodgkin’s lymphomas (NHL) comprise a group of extremely diverse lymphoproliferative neoplamas that have a predisposition for extranodal sites. Amongst the extranodal locations rare involvement of oral cavity has been reported and occurrence of these neoplasms on the cheek are thin on the ground. The most commonly encountered is the Diffuse large B-cell lymphoma. The B-cell neoplasms are clonal tumors of mature and immature B cells and the relatedness of B-cell lymphomas to normal B-cell counterparts forms a key aspect in their nomenclature of classification. Diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), consists of medium-sized to large B cells with a diffuse growth pattern. This lesion is a morphologically and molecularly heterogeneous entity which does not meet the diagnostic criteria of any specific large B-cell lymphoma neoplasms. Amongst the cases of DLBCL in n the head and neck region involvement of cheek/ buccal mucosa is scarce.

Primary Splenic Diffuse Large B-Cell Lymphoma: A Case Report.

The differential diagnosis of splenic nodules or infiltrates is vast and challenging, and it includes haematological diseases, systemic infectious diseases but also non-malignant infiltrative diseases.Although some lymphomas frequently present with splenomegaly, this is not the case of DLBCL, with the exception of PS-DLBCL.PS-DLBCL is a very rare pathology, accounting for 1% of all DLBCL and less than 1% of all NHL.

Dynamic changes in circulating EBV-DNA load during treatment have prognostic values in EBV+ DLBCL-NOS: a Chinese cohort study.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified (EBV+ DLBCL-NOS), is an EBV-positive clonal B-cell lymphoid proliferation and circulating EBV-DNA is a great indicator for prognosis among EBV associated disease. In this retrospective study, we report 66 EBV+ DLBCL cases among 2137 DLBCL-NOS cases diagnosed from 2013 to 2021 (prevalence of 6.0%). After a median follow-up of 27months, progression-free survival (PFS) and overall survival (OS) at 2years were 39.5% ± 6.2% and 53.6% ± 6.4%, respectively. Multivariate analysis showed that only the biomarker of the positivity of post treatment EBV-DNA had a borderline correlation with shorter PFS and OS (PFS: P = 0.053; OS: P = 0.065). Patients were divided into three subgroups according to dynamic changes of EBV-DNA status: EBV-DNA persistently negative group, EBV-DNA persistently positive group, and EBV-DNA transformed from positive to negative group; among the three groups, patients of the persistently positive group had worst PFS and OS (P = 0.0527 and P = 0.0139, respectively). Decline in EBV copies correlated significantly with treatment response as well. In conclusion, circulating EBV-DNA level played a vital role in prognostic and monitoring marker for EBV+ DLBCL-NOS.

IGH::CD274 (PD-L1) rearrangement in diffuse large B cell lymphoma and its therapeutic implication.

Diffuse large B cell lymphoma (DLBCL) expresses abundant programmed death ligand 1 (PD-L1), which shields tumor cells from immune attacks through the PD-L1/PD-1 signaling axis. The mechanism of PD-L1 overexpression includes the deletion of the 3'end of PD-L1, which increases its mRNA stability, and the gain or amplification of PD-L1. Previous studies found two cases of DLBCL carrying an IGH::PD-L1 by whole genome sequencing. We describe two more such cases by a targeted DNA next-generation sequencing (NGS) capable of detecting IGH rearrangements, leading to PD-L1 overexpression. DLBCL with PD-L1 overexpression is often resistant to R-CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine and prednisolone). Our patients responded to a combination of R-CHOP and a PD-1 inhibitor.

Abstract 1181: Etiologic heterogeneity of genetic risk for DLBCL cell-of origin molecular subtypes

Abstract Diffuse large B-cell lymphoma (DLBCL) is clinically and biologically heterogenous. Based on gene expression profiling of the tumor, DLBCL is classified into two major molecular subtypes linked to cell-of-origin (COO): germinal center (GCB) and activated B-Cell (ABC). The GCB subtype is characterized by a high prevalence of somatic mutations, particularly in apoptosis genes (e.g., BCL2) which is characteristic of follicular lymphoma (FL, another GCB lymphoma). The development of the validated NanoString gene expression test as well as immunohistochemistry markers that work in formalin-fixed, paraffin-embedded tissue allows for the classification of DLBCL by COO in epidemiological studies. We hypothesized that integration of COO with germline genetics could provide insight into the underlying biology driving this heterogeneity, as well as insight into putative function of germline risk variants. Prior genome wide association studies (GWAS) have identified 7 SNPs in 6 susceptibility loci for DLBCL, including: 2p23.3 (rs79480871 NCOA1), 3q13.33 (rs9831894 CD86), 3p24.1 (rs6773363 EOMES), 6p21.33 (rs2523607 HLA-B), 6p25.3 (rs116446171 EXOC2), and 8q24.21 (rs13255292 and rs4733601 PVT1 and MYC). Two of these loci were also identified in FL GWAS (different lead SNPs): 6p21.33 (rs3130437) and 8q24.21 (rs13254990 PVT1). Additional published FL susceptibility loci include: 3q28 (rs6444305 LPP), 6p21.32 (rs9268839), 11q23.3 (rs4938573 CXCR5), 11q24.3 (rs4937362 ETS1), and 18q21.33 (rs17749561 BCL2). Here we evaluated whether the published DLBCL/FL loci differ by COO molecular subtypes. We evaluated each of the 14 DLBCL/FL SNPs by case-case (GCB vs. nonGCB DLBCL) and polytomous case-control (GCB, nonGCB, and FL vs. controls) analyses. DLBCL cases were classified into GCB vs. nonGCB based on best available data from NanoString, RNAseq, followed by the Hans algorithm. A total of 778 DLBCL cases (470 GCB and 308 nonGCB), 1,050 FL cases, and 1,383 controls were analyzed. Odds ratios (OR) based on ordinal encoding of each SNP and 95% CI were calculated for each of the comparison groups. The ORs for four GWAS SNPs were significantly elevated in GCB vs. nonGCB DLBCL as well as in FL; two were FL GWAS SNPs from the HLA region (6p21.32 and 6p21.33) and the other two (BCL2 and ETS1) are important in the germinal center program. In contrast, one SNP (EXOC2) was significantly elevated in nonGCB-DLBCL and was not associated with GCB-DLBCL or FL; this SNP is also near IRF4 (MUM1), a gene important in the ABC program. For the remaining SNPs, there were suggestive associations for GCB-DLBCL and FL versus nonGCB DLBCL (CD86, CXCR5); nonGCB-DLBCL vs. GCB-DLBCL and FL (NCOA1, PVT1); and associations that showed no pattern with COO (EOMES, LPP, HLA-B and MYC). These findings provide insight into the shared pathogenesis of FL and GCB-DLBCL to inform etiologic mechanisms and risk assessment. Citation Format: Rosalie Griffin Waller, Dennis P. Robinson, Anne J. Novak, Lisa M. Rimsza, Kerstin Wenzl, Rebecca L. King, Andrew L. Feldman, Matthew J. Maurer, Grzegorz S. Nowakowski, Brian K. Link, Thomas M. Habermann, Susan L. Slager, James R. Cerhan. Etiologic heterogeneity of genetic risk for DLBCL cell-of origin molecular subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1181.

Signet ring cell-like diffuse large B-cell lymphoma involving the breast: a case report

BackgroundDiffuse large B-cell lymphoma (DLBCL) with signet ring cell components is extremely rare. Here, we present a case of DLBCL with signet ring cell components involving the breast, which can be easily confused with invasive lobular carcinoma of the breast or metastatic signet ring cell carcinoma of gastrointestinal origin.Case presentationA 66-year-old woman presented with a painless mass in her left breast. Enhanced magnetic resonance imaging (MRI) of the breast revealed a 42 × 29 × 28 mm mass in the left breast. Histological examination revealed a diffuse or scattered arrangement of round cells mixed with signet ring-like cells. Immunohistochemically, the neoplastic cells were positive for PAX-5, CD79a, CD20, Bcl-6, and MUM-1 but and negative for cytokeratin, ER, PR, E-cadherin, and P120. The Ki-67 proliferation index was approximately 70%. Fluorescence in situ hybridisation (FISH) demonstrated non-rearrangement of Bcl-2, Bcl-6, and c-MYC genes. Immunohistochemistry and FISH examination confirmed the diagnosis of DLBCL. Subsequently, immunofluorescence showed both IgM and IgG deposits in the signet ring-like lymphocytes. After confirming the diagnosis, the patient received four courses of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemotherapy in a specialist hospital and achieved partial remission; however, she unfortunately died of secondary pneumocystis pneumonia infection 3 months later.ConclusionMalignant lymphoma with signet ring cell morphology is quite uncommon, and this variant can be a diagnostic pitfall. We emphasise that pathologists should consider lymphoma in the differential diagnosis of malignant breast tumours.

Prognostic impact of miR-125b and miR-155b and their relationship with MYC and TP53 in diffuse large B-cell lymphoma: cell-of-origin classification matters.

Tumoral microRNAs, such as miR-125b and miR-155b, are important gene expression regulators with complex pathogenetic mechanisms. However, their role in DLBCL, especially when cell-of-origin classification is considered, are still to be elucidated. In a series of 139 DLBCL cases considering germinal center (GC) versus nonGC subtypes, we investigated miR-125b and miR-155b expression by in situ hibridization and their association with some immunophenotypic presentations, including MYC, BCL2 and TP53 expression, MYC, BCL2 and BCL6 translocation status, as well as clinicopathological features and outcomes. miR-125b detection was positively correlated to the Ki-67 index (P = 0.035) in the nGC. Considering the GC subgroup, the percentage of miR-125b positive cells was also correlated to either MYC and MYC/BCL2 double expression (P = 0.047 and P = 0.049, respectively). When it comes to nGC patients, miR-155b percentage and intensity, as well as Allred score, were positively correlated to disease progression (P = 0.038, P = 0.057 and P = 0.039, respectively). In a multivariate analysis, GC phenotype was a significant independent factor associated with higher OS (P = 0.007) and, considering the nGC group, although not significant, the expression of TP53, miR-125b and miR-155b seems to be potential prognostic biomarkers in these tumors. This study demonstrated different pathways based on cell-of-origin classification and highlighted different clinical outcomes. miR-125b, miR-155b and TP53 expression may also represent potential prognostic factors in nGC-DLBCL.

Ars2-containing bispecific, Fab- and IgG1-format BAR-bodies to target DLBCL cells.

Despite recent advances in the therapy of diffuse large B-cell lymphoma, not otherwise specified (DLBCL), around 30% of patients develop refractory disease or relapse after first-line treatment. Recently, Ars2 was reported as the auto-antigenic target of the B-cell receptor (BCR) in approximately 25% of activated B-cell DLBCL cases. Ars2 could be used to specifically target B cells expressing Ars2-reactive BCRs. However, the optimal therapeutic format to integrate Ars2 into has yet to be determined. To mimic therapeutic antibody formats, Ars2-containing bispecific and IgG1-like constructs (BCR antigens for reverse [BAR]-bodies) were developed. Two bispecific BAR-bodies connecting single-chain antibodies against CD16 or CD3 to the BCR-binding epitope of Ars2 were constructed. Both constructs showed strong binding to U2932 cells and induced effector cell-dependent and selective cytotoxicity against U2932 cells of up to 44% at concentrations of 20μg/ml. Additionally, IgG1-format Ars2 BAR-bodies were constructed by replacing the variable heavy- and light-chain regions of a full-length antibody with the Ars2 epitope. IgG1-format Ars2 BAR-bodies also bound selectively to U2932 and OCI-Ly3 cells and induced selective cytotoxicity of up to 60% at 10μg/ml. In conclusion, Ars2-containing bispecific and IgG1-format BAR-bodies both are new therapeutic formats to target DLBCL cells.